休克曾被认为是毛细血管灌注不足。多数休克病人的血管强烈收缩(仅心脏和脑除外),结果限制血流从动脉进入毛细血管。缩血管药则更使之加重。静脉补液时,小动脉往往松弛,血中儿茶酚胺浓度下降。但是,有些休克,特别伴有弥漫性血管内凝血时,小动脉则并不舒张,因为毛细血管内有微栓。这样即使经静脉充分补液也无反应。肺 Shock was once considered a capillary insufficiency. In most shock patients, the blood vessels contract strongly (except in the heart and brain) and as a result restrict the blood flow from the artery into the capillaries. Vasoconstrictor drugs are even more aggravated. Intravenous rehydration, arterioles tend to relax, the blood catecholamine concentration decreased. However, some shock, especially with disseminated intravascular coagulation, arterioles do not relax, because there are micro-capillaries in the capillary. This does not respond even if adequate intravenous fluids are rehydrated. lung